Most in baseball would call this the king of forearm exercises.
Stronger hands, wrists, forearms and overall grip have obvious benefits in baseball especially in swinging a bat but also can increase velocity and prevent injury by supporting the elbow.
Throwing a baseball requires plenty of wrist and finger snap. The stronger both are the more spin you can create on the ball – increasing velocity. Same with a bat. The stronger your hands and wrists are the more bat-speed you’ll have.